Cognitive Behavioral Stress Management (CBSM) interventions have been shown to decrease cancer-related distress, foster emotional growth and improve immune functioning during treatment for breast cancer. CBSM interventions use well-validated cognitive behavioral techniques such as relaxation and meditation training, cognitive restructuring, and communication skills training to increase active, adaptive coping and are typically delivered in a group setting. The present project aims to develop an online version of a CBSM intervention for women undergoing adjuvant treatment for early stage breast cancer. Phase I achievements included developing the user interface and two prototype modules of the web-based intervention. These two modules ("Introduction to Relaxation" and "Communication with Healthcare Providers") were created with Talaria's proprietary software, are highly interactive, and are presented in a multimedia format. Two usability studies, one in- person and one online, with 62 current and past cancer patients, demonstrated high levels of approval, satisfaction, and ease-of-use. In Phase II goals are to develop the entire intervention and examine its effectiveness in a randomized clinical trial. This 10-module intervention will consist of cognitive behavioral techniques adapted for web-presentation by Talaria's experienced eLearning team of clinicians, researchers, writers, programmers and multimedia experts. Each module will include self- assessment and targeted feedback, didactic psychoeducation, interactive exercises, and opportunities for self-monitoring-- all tailored to the needs of women with early stage breast cancer. In addition, guided written self-disclosure exercises will promote emotional expression and a discussion board will encourage group support. The web-based intervention will be usability tested and the final product will be evaluated in a randomized clinical trial with a sample of 120 women in adjuvant treatment for breast cancer. Women will be randomly assigned to use the 10-week intervention with biweekly telephone assessments or to the telephone assessments alone. Outcome measures include patients'confidence in their coping abilities, benefit finding, quality of life, and cancer-related distress. We plan to market this product directly to cancer patients, as well as to cancer care providers, hospitals, clinics and pharmaceutical companies that manufacture cancer medications. Public Health Relevance: Nearly 200,000 American women are diagnosed with breast cancer every year. As they go through cancer treatment, many patients experience a significant decline in their quality of life due to stress, treatment side effects, anxiety, depression, and relationship difficulties. We propose to develop a web-based version of Cognitive Behavioral Stress Management, an empirically supported intervention for women with breast cancer. This web intervention will be convenient, private and available for low cost to women regardless of location or insurance coverage.